Answer: Unfortunately, this is the most difficult time of year to be trying to seed a lawn. (The best time is later in the summer into early fall.) You may need to wait until a few days after a soaking rain so the ground is not quite so hard. Or, you could water it thoroughly with a sprinkler a few hours or the day before you try to till. (You can't till dry, hardened soil and you can't till overly wet, saturated soil.) The best amendment if you want to grow grass would be a layer of compost several inches thick worked into the the top six inches of soil. You should also run some basic soil tests to check the fertility and soil pH; then add fertilizer and/or lime according to the test results. Your state extension service should be able to help with the testing and interpreting the results. Here is their web site for contact information and additional information about lawn care.
Good luck with your lawn!
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